<!DOCTYPE html>
<html>
<head>
  <title>Bootstrap 实例 提示信息</title>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <link rel="stylesheet" href="https://cdn.staticfile.org/twitter-bootstrap/4.1.0/css/bootstrap.min.css">
  <script src="https://cdn.staticfile.org/jquery/3.2.1/jquery.min.js"></script>
  <script src="https://cdn.staticfile.org/popper.js/1.12.5/umd/popper.min.js"></script>
  <script src="https://cdn.staticfile.org/twitter-bootstrap/4.1.0/js/bootstrap.min.js"></script>
</head>
<body>

<button type="button" class="btn">基本按钮</button>
<button type="button" class="btn btn-primary">主要按钮</button>
<button type="button" class="btn btn-secondary">次要按钮</button>
<button type="button" class="btn btn-success">成功</button>
<button type="button" class="btn btn-info">信息</button>
<button type="button" class="btn btn-warning">警告</button>
<button type="button" class="btn btn-danger">危险</button>
<button type="button" class="btn btn-dark">黑色</button>
<button type="button" class="btn btn-light">浅色</button>
<button type="button" class="btn btn-link">链接</button>
</body>
</html>